Field of the Invention
The present invention relates to a speaker apparatus suitable for use at a location exposed to water droplets and a speaker box which forms the speaker apparatus.
Description of the Related Art
For conventional speaker apparatuses placed outdoors or indoors, the constant voltage system is employed in many cases in order to prevent power loss over long-distance transmission. In the constant voltage system, as indicated in FIG. 5, an amplifier 1 for amplifying sound signals is provided and a plurality of speaker apparatuses 2 are connected to an output terminal of the amplifier in parallel so that large-amplitude sound signals will be output from the amplifier 1 to the speaker apparatuses 2. For instance, sound signals having the amplitude of 100 volts are supplied to the speaker apparatuses 2. Each speaker apparatus 2 has a step-down transformer 2a so that the step-down transformer 2a will convert input sound signals into sound signals for use in a common speaker (for instance, a speaker of 4Ω or 8Ω) and will supply the converted signals to its corresponding speaker 2b. 
As indicated in Japanese Patent Publication No. 4560792, the speaker apparatus of this type has a bass reflex port in a speaker box in order to enhance bass sound properties. Normally, the bass reflex port is shaped like a cylinder so that one end of the bass reflex port is open outside the speaker box, with the other end being open inside the speaker box.